The present invention relates generally to a sterilized package of liquid nutritional product, and more specifically to one which has been sterilized aseptically and which contains infant formula.
For years, packaging of food products for storage and distribution has been primarily conducted in glass or metal containers. The costs associated with these containers, their closures, and their labels have increased and are projected to continue to rise. Utilization of thermoplastic materials would conserve more energy on a packaging and distribution systems basis. Additionally, the costs would not be as great. Therefore, it is extremely desirable to provide food products packaged in thermoplastic materials.
In the area of liquid nutritional products, packaging of such products for ambient temperature storage and distribution have increasingly utilized thermoplastics. In general, there are two approaches to the packaging of food products in a container. The first method utilizes retorting, whereby a food is placed into a container, the container is sealed, and then the container and product are subjected to heat, such that the product is sterilized. In the second method, a container is subjected to a sterilizing process prior to its receiving sterilized food product. Conventional processes for sterilizing containers in which food stuff is subsequently packaged include UV irradiation, treatment with a mixture of steam and air, and an aseptic technique in which the interior wall of the container is sprayed with hydrogen peroxide and subsequently dried.
It can be appreciated that because of the heat sensitivity of many thermoplastics, conventional retort sterilization techniques can damage or destroy many thermoplastic packages of the type containing food product under ambient conditions for prolonged periods. On the other hand, application of aseptic packaging would permit increased usage of thermoplastic packaging materials, since application of aseptic techniques would leave the package unaltered and undamaged. Additionally, food products subjected to aseptic packaging involves minimal alteration of the food product by processing, thereby potentially yielding a higher-quality end product.
U.S. Pat. No. 4,742,667 discloses a method of an apparatus for aseptic packaging. The general components of the system shown in that particular patent are typical of the component in many aseptic sterilization systems. In operation, a food product package arrives at a sterilization station. Hydrogen peroxide or another suitable disinfectant is applied to the inner surface of the container. Often times, the application involves atomization of a liquid so that a mist is applied. After application of the disinfectant, the container is transported along a conveyor, during which transport the food product container is subjected to additional sprayings of hot air.
Although disposable feeding packages for liquid nutritional products, especially infant formula and sterile water for infants, are desirable, heretofore such containers have only utilized the retort sterilization technique. The desirability of such a product cannot be underestimated since it can be used in a nursing system so as to eliminate the need for sterilizing bottles and other time-consuming tasks related to the feeding of infants. Such a package would be extremely desirable when an infant is away from home, for example at a day care center or during travel.
Examples of plastic containers that have been employed in the area of retortable packages are disclosed in published PCT application WO 90/14066. However, that particular reference neither teaches a method of manufacturing for use in retort conditions and is devoid of any disclosure or suggestion as to how, or even if, that particular disposable pre-sterilized feeding package may be used in an aseptic sterilization system. With respect to the closure for the top of the container, a number of closures are disclosed in U.S. Pat. No. 5,004,111, although the discussion of that particular closure omits any discussion of potential use in aseptic situations.
It is thus apparent that the need exists for an aseptically sterilized package of liquid nutritional product, specifically infant formula.